// 实现这个项目的构建任务

// 1. 转换js、scss、html、image、font、public
// 2. 创建本地开发服务、监听文件热更新
// 3. 上线准备，文件清空、文件压缩
const data = require('./data');

const { src, dest, series, parallel, watch } = require('gulp');
const del = require('del');
const browserSync = require('browser-sync');
const loadPlugins = require('gulp-load-plugins');

const plugins = loadPlugins();
const bs = browserSync.create();

const clean = () => {
  return del(['dist', 'temp']);
}

const style = () => {
  return src('src/assets/styles/*.scss', { base: 'src' })
    .pipe(plugins.sass())
    .pipe(dest('temp'))
    .pipe(bs.reload({ stream: true }))
}

const script = () => {
  return src('src/assets/scripts/*.js', { base: 'src' })
    .pipe(plugins.babel({ presets: ['@babel/preset-env'] }))
    .pipe(dest('temp'))
    .pipe(bs.reload({ stream: true }))
}

const page = () => {
  return src('src/*.html', { base: 'src' })
    .pipe(plugins.swig({ data, defaults: { cache: false } }))
    .pipe(dest('temp'))
    .pipe(bs.reload({ stream: true }))
}

const image = () => {
  return src('src/assets/images/**', { base: 'src' })
    .pipe(plugins.imagemin())
    .pipe(dest('dist'))
}

const font = () => {
  return src('src/assets/fonts/**', { base: 'src' })
    .pipe(plugins.imagemin())
    .pipe(dest('dist'))
}

const extra = () => {
  return src('public/**', { base: 'src'})
    .pipe(dest('dist'))
}

const serve = () => {
  watch('src/assets/styles/*.scss', style);
  watch('src/assets/scripts/*.js', script);
  watch('src/*.html', page);
  watch([
    'src/assets/images/**',
    'src/assets/fonts/**',
    'public/**'
  ], bs.reload);

  bs.init({
    notify: false,
    port: 8082,
    server: {
      baseDir: ['temp', 'src', 'public'],
      routes: {
        '/node_modules': 'node_modules'
      }
    }
  })
}

const useref = () => {
  return src('temp/*.html', { base: 'temp'})
    .pipe(plugins.useref({ searchPath: ['temp', '.'] }))
    .pipe(plugins.if(/\.js$/, plugins.uglify()))
    .pipe(plugins.if(/\.css$/, plugins.cleanCss()))
    .pipe(plugins.if(/\.html$/, plugins.htmlmin({
      collapseWhitespace: true,
      minifyCSS: true,
      minifyJS: true,
    })))
    .pipe(dest('dist'))
}

const compile = parallel(style, script, page);

const start = series(compile, serve);

const build = series(
  clean,
  parallel(
    series(compile, useref),
    image,
    font,
    extra
  )
)


module.exports = {
  clean,
  start,
  build,
}